Power Modules Having Current Sensing Circuits

ABSTRACT

According to some aspects of the present disclosure, power modules having current sensing circuits, and corresponding sensing methods, are disclosed. Example power modules include a printed circuit board (PCB) having a PCB trace, a first sense terminal coupled to the PCB trace at a first location, and a second sense terminal coupled to the PCB trace at a second location such that a resistance between the first and second sense terminals is defined by a resistance of the PCB trace between the first location and the second location. The power module further comprises a control coupled to the first sense terminal and the second sense terminal, the control adapted to measure a voltage between the first sense terminal and the second sense terminal and determine a current through the PCB trace based on the measured voltage and the resistance between the first sense terminal and the second sense terminal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. applicationSer. No. 15/753,492 filed Feb. 19, 2018, which claims the benefit of andpriority to PCT/CN2016/091809 filed Jul. 26, 2016. The entiredisclosures of the above applications are incorporated herein byreference.

FIELD

The present disclosure relates to power modules having current sensingcircuits, and corresponding sensing methods.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

Many power modules use different approaches for sensing current in thepower module, including current sensing transformers, alternatingcurrent (AC) sensors, output choke direct current resistance (DOR),shunt resistors, etc. High density, high power, space restricted powermodules often require small footprint components for current sensing inorder to increase available space for other components of the powermodule.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

According to one example embodiment of the present disclosure, a powermodule comprises a printed circuit board (PCB) having a PCB trace, afirst sense terminal coupled to the PCB trace at a first location, and asecond sense terminal coupled to the PCB trace at a second locationdistinct from the first location such that a resistance between thefirst sense terminal and the second sense terminal is defined by aresistance of the PCB trace between the first location and the secondlocation. The power module further comprises a control coupled to thefirst sense terminal and the second sense terminal, the control adaptedto measure a voltage between the first sense terminal and the secondsense terminal and determine a current through the PCB trace based onthe measured voltage and the resistance between the first sense terminaland the second sense terminal.

According to another example embodiment of the present disclosure, apower module comprises a printed circuit board (PCB) having a PCB trace,a first sense terminal coupled to a first location of the PCB trace, anda second sense terminal coupled to a second location of the PCB tracesuch that a resistance between the first sense terminal and the secondsense terminal is defined by a resistance of the PCB trace. The powermodule further comprises a control coupled to the first sense terminaland the second sense terminal, the control adapted to determine acurrent through the PCB trace based on a measured voltage between thefirst sense terminal and the second sense terminal and based on theresistance between the first sense terminal and the second senseterminal. The power module also comprises a temperature compensationcircuit coupled to the control, the temperature compensation circuitadapted to adjust an overcurrent protection threshold of the powermodule based on a measured ambient temperature to compensate for changesin the resistance between the first sense terminal and the second senseterminal based on temperature.

According to yet another example embodiment of the present disclosure,method of sensing a current sensing using a current sensing circuit, thecurrent sensing circuit having a first sense terminal coupled to aprinted circuit board (PCB) trace on a PCB of a power module and havinga second sense terminal coupled to the PCB trace such that a resistancebetween the first sense terminal and the second sense terminal isdefined by the resistance of the PCB trace. The method comprisesmeasuring a voltage between the first sense terminal and the secondsense terminal and determining a current through the PCB trace based onthe measured voltage and the resistance between the first sense terminaland the second sense terminal.

Further aspects and areas of applicability will become apparent from thedescription provided herein. It should be understood that variousaspects of this disclosure may be implemented individually or incombination with one or more other aspects. It should also be understoodthat the description and specific examples herein are intended forpurposes of illustration only and are not intended to limit the scope ofthe present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a block diagram of an example non-dissipative current sensingcircuit according to one embodiment of the present disclosure.

FIG. 2 is a side view of the circuit of FIG. 2 disposed on a printedcircuit board (PCB).

FIG. 3 is a block diagram of another example non-dissipative currentsensing circuit including a temperature compensation circuit.

FIG. 4 is a waveform of a predefined temperature coefficient curve foradjusting an overcurrent protection threshold.

FIG. 5 is a block diagram of another example non-dissipative currentsensing circuit having sense terminals coupled to a PCB trace.

FIG. 6 is a circuit diagram of another example non-dissipative currentsensing circuit, according to another embodiment of the presentdisclosure.

FIG. 7 is a circuit diagram of an example temperature compensationcircuit, according to another embodiment of the present disclosure.

Corresponding reference numerals indicate corresponding featuresthroughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. R will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

A power module according to one example embodiment of the presentdisclosure is illustrated in FIG. 1 and indicated generally by referencenumber 100. As shown in FIG. 1, the power module 100 includes a firstsense terminal 102 coupled to a printed circuit board (PCB) trace 106 ona PCB of a power module. The PCB trace 106 is coupled to an output chokeinductor 108 mounted to the PCB.

A second sense terminal 104 is coupled to an output pin 110 of the PCBpower module. The output pin 110 is connected to the PCB trace 106.Accordingly, a resistance between the first sense terminal 102 and thesecond sense terminal 104 is defined by the resistance of the PCB trace106 and the resistance of the output pin 110.

The power module 100 also includes a control 112 coupled to the firstsense terminal 102 and the second sense terminal 104. The control 112 isadapted to measure a voltage between the first sense terminal 102 andthe second sense terminal 104. The control 112 is adapted to determine acurrent through the PCB trace 106 and the output pin 110 based on themeasured voltage between the first sense terminal 102 and the secondsense terminal 104, and the resistance between the first sense terminaland the second sense terminal.

Accordingly, the control 112 can use the sensed voltage between thefirst sense terminal 102 and the sense terminal 104 to determine acurrent through the output choke inductor 108, because the output chokeinductor is coupled to the PCB trace 106 and the output pin 110.

The current sensing circuit (e.g., sense terminals 102, 104 and control112) of power module 100 is similar to a traditional shunt resistorcurrent sensing circuit, but may not require a shunt resistor. The powermodule 100 uses the resistance defined between the first sense terminal102 and the second sense terminal 104 (i.e. the resistance of the PCBtrace 106 and the output pin 110) to determine a current of the outputchoke inductor 108.

The current sensing circuit of the power module 100 can be consideredsubstantially non-dissipative (e.g., minimally dissipative, etc.)because the current sensing circuit may not introduce any additionalresistances to the current path of the power module, thereby increasingefficiency of the power module. For example, the current sensing circuitmay provide reduced power dissipation (e.g., a reduction of about 0.5 W,etc.) compared to traditional current sensing topologies.

The current sensing circuit may comprise less space on the PCB ascompared to traditional current sensing circuits, thereby increasingavailable space for other components of the power module (e.g., allowfor larger semiconductors, gate drivers, power transformers, outputchokes, input and output capacitors, etc.).

FIG. 2 illustrates a side view of the power module 100 including a PCB114. As shown in FIG. 2, the output choke inductor 108 and PCB trace 106are disposed on a top side of the PCB 114. The first sense terminal 102is also disposed on the top side of the PCB 114.

The output pin 110 is a through hole output pin extending through thePCB 114 to couple the top side of the PCB with the bottom side of thePCB. The second sense terminal 104 is disposed on the bottom side of thePCB 114.

Accordingly, the first sense terminal 102 and the second sense terminal104 are disposed on opposite skies of the PCB 114. Therefore, theresistance between the first sense terminal 102 and the second senseterminal is defined by the PCB trace 106 and the through hole output pin110 from the top side of the PCB 114 to the bottom side of the PCB 114.

Although FIG. 2 illustrates the output choke inductor 108, first senseterminal 102 and PCB trace disposed on a first side of the PCB 114, andthe second sense terminal 104 disposed on a bottom side of the PCB, itshould be apparent that other embodiments may include componentsdisposed on the same side of the PCB, on different skies of the PCB withrespect to one another, etc. Similarly, although FIG. 2 illustrates theoutput pin 110 as a through hole output pin extending through the PCB114 from a top side to a bottom side, other embodiments may include anoutput pin located on a single side of the PCB.

In some embodiments, the resistance between the first sense terminal 102and the second sense terminal 104 may include additional elements. Forexample, solder material may be used to couple the through hole outputpin 110 to the PCB 114, the PCB trace 106, etc. The resistance betweenthe first sense terminal 102 and the second sense terminal 104 mayinclude the resistance of the solder material.

In some embodiments, output vias may be used to couple the through holeoutput pin 110 to the PCB 114, the PCB trace 106, etc. The resistancebetween the first sense terminal 102 and the second sense terminal 104may include the resistance of the output vias.

In some embodiments, more than one through hole output pin 110 may beused. The resistance between the first sense terminal 102 and the secondsense terminal 104 may include the resistance of the multiple throughhole output pins.

Accordingly, the resistance between the first sense terminal 102 and thesecond sense terminal 104 may be defined by any suitable combination ofthe PCB trace resistance, the through hole output pin resistance, and aresistance of any additional components, materials, elements, etc.coupled to and/or between the PCB trace 106 and the through hole outputpin 110.

As should be apparent, the power module 100 may be any suitable powermodule. For example, the power module could be a switched-mode powersupply. The power module may include a high density PCB power module, aspace restricted application, etc. The PCB 114 may have any suitablesize such as a one-sixteenth inch thickness, a one-thirty-second inchthickness, etc. Some example dimensions for the PCB 114 may include athirty three millimeter length, a 22.8 millimeter width, etc. As shouldbe apparent, other PCBs may include other suitable dimensions.

The output choke inductor 108 may be any suitable choke inductor capableof reducing an output voltage ripple of the power module.

The PCB trace 106 can be any suitable PCB trace capable of conducting acurrent. The PCB trace 106 may be disposed on the PCB using anysuitable, etching, depositing, etc. techniques. The PCB trace 106 maycomprise any suitable conductor material, including but not limited tocopper, etc. Similarly, the through hole output pin 110 can be anysuitable conductor capable of supplying current to a load connected tothe output pin. The output pin 110 may include any suitable conductmaterial, including but not limited to copper, etc.

The sense terminals 102 and 104 can be any suitable connectors capableof sensing a voltage at the PCB trace 106, the output pin 110, etc. Forexample, the sense terminals may include a PCB trace connection, aconductive terminal, etc.

FIG. 3 illustrates another power module 300 according to another exampleembodiment of the present disclosure. The module 300 is similar tomodule 100 of FIG. 1, but includes a temperature compensation circuit116 coupled to the control 112. The temperature compensation circuit 116is adapted to measure an ambient temperature (e.g., a temperature aroundthe compensation circuit, a temperature around the PCB trace 106, atemperature around the power module, etc.). The temperature compensationcircuit 116 then adjusts an overcurrent protection threshold of thepower module based on the measured ambient temperature to compensate forchanges in the resistance between the first sense terminal 102 and thesecond sense terminal 104 based on temperature.

The control 112 may be adapted to compare the determined current throughthe PCB trace 106 and the output pin 110 to the adjusted overcurrentprotection threshold to control operation of the power module. Forexample, the control 112 may adjust switching, stop switching, etc. ofthe power module if the measure current exceeds the adjusted overcurrent protection threshold.

As shown in FIG. 3, the temperature compensation circuit 116 includes athermistor 118. The thermistor 118 may be any suitable thermistor,including a negative-temperature coefficient (NTC) thermistor, etc.

The temperature compensation circuit 116 may be adapted to adjust theovercurrent protection threshold by comparing the measured ambienttemperature to a predefined temperature coefficient curve. An examplepredefined temperature coefficient curve 403 is illustrated in FIG. 4.

The temperature compensation circuit 116 may compare the measuredambient temperature to the temperature coefficient curve 403 todetermine an adjustment value of the overcurrent protection threshold tocompensate for changes in resistance between the first sense terminal102 and the second sense terminal 104 due to variations in temperatureof the PCB trace 106 and the output pin 110. For example, thetemperature coefficient curve 403 may represent variations in theresistance between the first sense terminal 102 and the second senseterminal (Le., variations in the resistance of the PCB trace 106, theoutput pin 110, etc.) due to variations in temperature of the PCB trace106, the output pin 110, etc.

The overcurrent protection threshold can be any suitable threshold forprotecting the power module, load, etc. from conducting an amount ofcurrent that may damage the power module, load, etc. In someembodiments, the overcurrent protection threshold may be between 110%and 130% of a rated output current of the power module.

The overcurrent protection threshold may be adjusted based on the sensedtemperature, then compared with the sensed output current withoutcalibration of the sensed output current. As the temperature slowlyvaries, the overcurrent protection threshold can be changed slowly tokeep pace with the change in temperature. In some embodiments, theovercurrent protection threshold may be changed approximately everytwenty standard interrupts of the control 112.

The predefined temperature coefficient curve 403 may be divided intomultiple regions. As shown in FIG. 4, the temperature coefficient curve403 is divided into three regions. A first region includes ambienttemperatures below a low temperature threshold 405, a second regionincludes ambient temperatures between the low temperature threshold anda high temperature threshold 407, and a third region includes ambienttemperatures above the high temperature threshold.

FIG. 4 illustrates the temperature coefficient curve 403 as spanning arange from about negative forty degrees Celsius to about one hundred andtwenty five degrees Celsius, having the low temperature threshold atabout zero degrees Celsius and having the high temperature threshold atabout one hundred degrees Celsius. It should be apparent however thatother embodiments may be divided into more or less (or none) regions,may span different temperature ranges, may have different lowtemperature thresholds, different high temperature thresholds, etc.

Each region of the predefined temperature coefficient curve 403 mayinclude different values for adjusting the overcurrent protectionthreshold. Where the measured ambient temperature has a smaller effecton the overcurrent protection threshold, a constant value may be used,the overcurrent protection threshold may be changed slowly, etc. Forexample, below the temperature threshold 405, the effect of temperatureon the resistance of the PCB trace 106 and output pin 110 changesslowly, so a fixed minimum threshold may be used to adjust theovercurrent protection threshold. Similarly, above the high temperaturethreshold 407, the effect of temperature on the resistance of the PCBtrace 106 and output pin 110 changes slowly, so a fixed maximumthreshold may be used to adjust the overcurrent protection threshold.

In other regions where the overcurrent protection threshold changes morerapidly with variations in ambient temperature, scaled adjustments tothe overcurrent protection threshold may be used. For example, betweenthe low temperature threshold 405 and the high temperature threshold407, the overcurrent protection threshold value may be scaled linearlywith changes in the measured ambient temperature.

Different PCBs may have variations in overcurrent protection thresholdsbased on PCB manufacturing, assembly processes, variation in components,etc. The variations may be within about twenty percent from PCB to PCB.The variations may be automatically adjusted by trimming the baseovercurrent protection threshold value. Therefore, an actual overcurrentprotection threshold value may be equal to a base overcurrent protectionthreshold offset, plus a variable temperature compensation duringoperation. This calibration may allow the overcurrent protectionthreshold variations to be reduced despite the manufacturing, assembly,component, etc. variations. For example, the variations may be reducedto plus or minus ten percent. Dividing the temperature coefficient curveinto more regions can increase the accuracy of overcurrent protectionthreshold adjustments.

FIG. 5 illustrates another power module 500 according to another exampleembodiment of the present disclosure. The module 500 is similar tomodule 100 of FIG. 1, but the second sense terminal 104 is coupled tothe PCB trace 106 instead of an output pin. The second sense terminal104 is coupled to the PCB trace 106 at an end of the PCB trace oppositethe first sense terminal 102. Therefore, a resistance defined betweenthe first sense terminal 102 and the second sense terminal 104 isdefined by a resistance of the PCB trace 106.

The control 112 is adapted to measure a voltage between the first senseterminal 102 and the second sense terminal 104, and to determine acurrent through the PCB trace 106 based on the measured voltage and theresistance between the first sense terminal and the second senseterminal.

The module 500 also includes a temperature compensation circuit 116coupled to the control 112. The temperature compensation circuit 116 isadapted to measure an ambient temperature and adjust an overcurrentprotection threshold of the power module based on the measured ambienttemperature to compensate for changes in the resistance between thefirst sense terminal 102 and the second sense terminal 104 based ontemperature.

The control 112 may be adapted to compare the determined current throughthe PCB trace 106 to the adjusted overcurrent protection threshold tocontrol operation of the power module.

The temperature compensation circuit 116 may include a thermistor 118.The thermistor 118 can be any suitable thermistor, including but notlimited to an NTC thermistor, etc.

FIG. 6 illustrates a wiring diagram of an example power module 600,according to another example embodiment of the present disclosure. Themodule 600 includes a first sense terminal 602 and a second senseterminal 604 coupled about a PCB trace 606. The module 600 also includesan output choke inductor 608.

Control 612 is adapted to measure a voltage between the first senseterminal 602 and the second sense terminal 604, and to determine acurrent through the output choke inductor 608 based on the measuredvoltage and a resistance between the first sense terminal and the secondsense terminal. For example, resistor R5, capacitor C3, and resistor R13are coupled between the first sense terminal 602 and the second senseterminal 604. The control 612 is coupled to the capacitor C3 to measurea voltage across the capacitor C3, corresponding to a voltage betweenthe first sense terminal 602 and the second sense terminal 604.

The example component values, tolerances, etc. illustrated in FIG. 6 areincluded for purposes of illustration only, and it should be apparentthat other suitable components values, tolerances, etc. can be useswithout departing from the scope of the present disclosure.

FIG. 7 illustrates a wiring diagram of an example temperaturecompensation circuit 716, according to another example embodiment of thepresent disclosure. The temperature compensation circuit 716 includes anegative temperature coefficient thermistor 718.

The temperature compensation circuit 716 is adapted to measure anambient temperature for adjusting an overcurrent protection threshold ofa power module. For example, the temperature compensation circuit 716may be coupled to the control 612 of FIG. 6, such that the control canmodify operation of a power module based on the determined currentbetween sense terminal 602 and sense terminal 604 and the measuredambient temperature and adjusted overcurrent protection threshold fromtemperature compensation circuit 716.

The example component values, tolerances, etc. illustrated in FIG. 7 areincluded for purposes of illustration only, and it should be apparentthat other suitable components values, tolerances, etc. can be useswithout departing from the scope of the present disclosure.

In another embodiment, a method of sensing current using a currentsensing circuit is disclosed. The current sensing circuit includes afirst sense terminal coupled to a printed circuit board (PCB) trace on aPCB of a power module. The PCB trace is coupled to an output chokeinductor mounted to the PCB. A second sense terminal is coupled to atleast one output pin of the power module. The output pin is connected tothe PCB trace such that a resistance between the first sense terminaland the second sense terminal is defined by the resistance of the PCBtrace and the resistance of the output pin. The method generallyincludes measuring a voltage between the first sense terminal and thesecond sense terminal, and determining a current through the PCB traceand the output pin based on the measured voltage and the resistancebetween the first sense terminal and the second sense terminal. Themethod also includes measuring an ambient temperature of the powermodule, and adjusting an overcurrent protection threshold of the powermodule based on the measured ambient temperature to compensate forchanges in the resistance between the first sense terminal and thesecond sense terminal based on temperature.

The method may also include comparing the determined current through thePCB trace and the output pin to the adjusted overcurrent protectionthreshold to control operation of the power module.

In some embodiments, the first side of the PCB is a top side of the PCB,and the second side of the PCB is a bottom side of the PCB opposite thetop side of the PCB, and the output pin includes a through hole outputpin connecting the top side of the PCB to the bottom side of the PCB. Asolder material may be soldered to the output pin, such that theresistance defined between the first sense terminal and the second senseterminal further includes the resistance of the solder material.

Adjusting the overcurrent protection threshold may include comparing themeasured ambient temperature to a predefined temperature coefficientcurve. The temperature coefficient curve may include at least threeseparately defined regions.

Comparing the measured ambient temperature to a predefined temperaturecoefficient curve may include linearly scaling the overcurrentprotection threshold when the measured ambient temperature is between alow temperature threshold and a high temperature threshold. Comparingthe measured ambient temperature to the predefined temperaturecoefficient curve may include selecting a minimum overcurrent protectionthreshold value when the measured ambient temperature is below the lowtemperature threshold. Comparing the measured ambient temperature to thepredefined temperature coefficient curve may include selecting a maximumovercurrent protection threshold value when the measured ambienttemperature is above the high temperature threshold.

Any of the example embodiments and aspects disclosed herein may be usedin any suitable combination with any other example embodiments andaspects disclosed herein without departing from the scope of the presentdisclosure. For example, current sensing circuits and temperaturecompensation circuits described herein may implement other sensingmethods, the sensing methods described herein may be implemented inother current sensing circuits, temperature compensation circuits, etc.without departing from the scope of the present disclosure.

Any of the controls, circuits, methods, etc. described herein may beconfigured, adapted, etc. according to any suitable hardware and/orsoftware implementations. For example, the controls, circuits, etc. mayinclude a microprocessor, digital signal processor, etc. configured toexecute computer-executable instructions stored in memory on aprocessor, may include logic circuitry, etc. adapted to perform one ormore instructions, etc.

Example embodiments and aspects of the present disclosure may provideany of the following advantages, including but not limited to:simplified circuit design, simplified power module design, reduced cost,reduced component count, increased power module efficiency, higher powermodule density, increase PCB space availability, elimination of a shuntsensing resistor, etc.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

What is claimed is:
 1. A power module comprising: a printed circuitboard (PCB) having a PCB trace; a first sense terminal coupled to thePCB trace at a first location; a second sense terminal coupled to thePCB trace at a second location distinct from the first location suchthat a resistance between the first sense terminal and the second senseterminal is defined by a resistance of the PCB trace between the firstlocation and the second location; and a control coupled to the firstsense terminal and the second sense terminal, the control adapted to:measure a voltage between the first sense terminal and the second senseterminal; and determine a current through the PCB trace based on themeasured voltage and the resistance between the first sense terminal andthe second sense terminal.
 2. The module of claim 1, wherein the firstsense terminal is disposed on a first side of the PCB, and the secondsense terminal is disposed on a second side of the PCB.
 3. The module ofclaim 2, wherein the first side of the PCB is a top side of the PCB, andthe second side of the PCB is a bottom side of the PCB opposite the topside of the PCB.
 4. The module of claim 1, further comprising an outputpin coupled to the PCB; wherein the PCB trace is coupled between thefirst sense terminal and the output pin; wherein the second location islocated on the output pin; and wherein the resistance between the firstsense terminal and the second sense terminal is further includes aresistance of the output pin.
 5. The module of claim 4, wherein theoutput pin includes a through hole output pin connecting a top side ofthe PCB to a bottom side of the PCB.
 6. The module of claim 4, furthercomprising a solder material soldered to the output pin, such that theresistance defined between the first sense terminal and the second senseterminal further includes the resistance of the solder material.
 7. Themodule of claim 1, further comprising a temperature compensation circuitcoupled to the control, the temperature compensation circuit adapted to:measure an ambient temperature; and adjust an overcurrent protectionthreshold of the power module based on the measured ambient temperatureto compensate for changes in the resistance between the first senseterminal and the second sense terminal based on temperature.
 8. Themodule of claim 7, wherein the control is adapted to compare thedetermined current through the PCB trace to the adjusted overcurrentprotection threshold to control operation of the power module.
 9. Themodule of claim 7, wherein the temperature compensation circuit isadapted to adjust the overcurrent protection threshold by comparing themeasured ambient temperature to a predefined temperature coefficientcurve.
 10. The module of claim 1, further comprising an output chokeinductor mounted to the PCB and coupled to the PCB trace; and whereinthe current through the PCB trace comprises a current through the outputchoke inductor.
 11. A power module comprising: a printed circuit board(PCB) having a PCB trace; a first sense terminal coupled to a firstlocation of the PCB trace; a second sense terminal coupled to a secondlocation of the PCB trace such that a resistance between the first senseterminal and the second sense terminal is defined by a resistance of thePCB trace; a control coupled to the first sense terminal and the secondsense terminal, the control adapted to determine a current through thePCB trace based on a measured voltage between the first sense terminaland the second sense terminal and based on the resistance between thefirst sense terminal and the second sense terminal; and a temperaturecompensation circuit coupled to the control, the temperaturecompensation circuit adapted to adjust an overcurrent protectionthreshold of the power module based on a measured ambient temperature tocompensate for changes in the resistance between the first senseterminal and the second sense terminal based on temperature.
 12. Themodule of claim 11, wherein the control is further adapted to comparethe determined current through PCB trace to the adjusted overcurrentprotection threshold to control operation of the power module.
 13. Themodule of claim 11, wherein the control is further adapted to measurethe voltage between the first sense terminal and the second senseterminal; and wherein the temperature compensation circuit is furtheradapted to measure the ambient temperature.
 14. The module of claim 11,further comprising an output choke inductor mounted to the PCB andcoupled to the PCB trace; and wherein the first location is adjacent tothe output choke inductor.
 15. A method of sensing a current sensingusing a current sensing circuit, the current sensing circuit having afirst sense terminal coupled to a printed circuit board (PCB) trace on aPCB of a power module and having a second sense terminal coupled to thePCB trace such that a resistance between the first sense terminal andthe second sense terminal is defined by the resistance of the PCB trace,the method comprising: measuring a voltage between the first senseterminal and the second sense terminal; determining a current throughthe PCB trace based on the measured voltage and the resistance betweenthe first sense terminal and the second sense terminal.
 16. The methodof claim 15, further comprising measuring an ambient temperature of thepower module; and adjusting an overcurrent protection threshold of thepower module based on the measured ambient temperature to compensate forchanges in the resistance between the first sense terminal and thesecond sense terminal based on temperature.
 17. The method of claim 15,further comprising comparing the determined current through the PCBtrace to the adjusted overcurrent protection threshold to controloperation of the power module.
 18. The method of claim 15, wherein thepower module further comprises an output pin connected to the PCB andcoupled to the second sense terminal; and wherein the resistance definedbetween the first sense terminal and the second sense terminal furtherincludes a resistance of the output pin.
 19. The method of claim 18,wherein a first side of the PCB is a top side of the PCB; wherein asecond side of the PCB is a bottom side of the PCB opposite the top sideof the PCB; and wherein the output pin includes a through hole outputpin connecting the top side of the PCB to the bottom side of the PCB.20. The method of claim 18, further comprising a solder materialsoldered to the output pin; and wherein the resistance defined betweenthe first sense terminal and the second sense terminal further includesa resistance of the solder material.